Bad Spark Plug Help

[gr8vet]

Hey guys, just rolled in from the Power tour. About 1500 miles into the trip engine went to crap and found two bad plugs. In the middle of the backwoods of Virginia no less. Otherwise a Great trip.

I have an Edlebrach carb and manifold. The two plugs where at # 4 and #3. Any suggestions why fail at these locations? I did go to a colder plug when I swapped.

 

[big2bird]

Check the plug wires, and check to see if any of those plugs have broken/cracked porcelin. If you hear them "tink" when you install them, they are done, no matter how "good" they look.

 

[big_G]

Looks like those 2 plugs are oil fouled. How old is the engine build?. I suspect valve guides and valve guide seals.

 

[big2bird]

Looks like those 2 plugs are oil fouled. How old is the engine build?. I suspect valve guides and valve guide seals.

I would agree after verifying they were working well. Iv'e had bad wires cause the same thing.

 

[gr8vet]

Thanks guys. We rebuilt the engine about two years ago, all new wet parts and used supposedly good Comp Cam Valve guide seals. The engine had less than 1000 miles on it when I left for this trip. So what you see is 2500 miles.

I know that sometimes these things just happen, but I found it strange that they were at opposing sides of engine and intake. If we found only one plug bad, or at #1 and # 6 it would not appear so interesting. Guess it is possible to have messed up both of these valve guides and be mere coincidence they are at opposing sides.

If we got the springs a bit too tight and the valves were not closing completely, could that cause this same issue? I know I have just a bit of tinging on the valve train.

Thanks again!

tt

BTW, Kudos to my new Indiana friend, whom I have never met, offered and went and grabbed me a set of plugs. Very nice folks on these trips.

 

[big_G]

My second guess would be intake gasket. Hard to verify without pulling the intake manifold.

 

[gr8vet]

Could very well be the intake, I am seeing a lot of oil around front and rear after this trip. Going to pull, paint, look, fix, hopefully. Thanks for all the things to look for.

tt